Abstract
Ninety-six, 35 day old, crossbred pigs, were fed either a basal diet based on com, soybean meal, fish meal and whey or one of three similar diets supplemented with either 0.5% organic acid or enzyme both alone and in combination. Neither organic acid nor enzyme produced any significant (p<0.05) improvements in daily gain or feed conversion. Organic acid, both alone and in combination with enzyme, significantly (p=0.04) decreased the pH in the lower colon. None of the treatments produced any effects on E. Coli or Lactobacillus numbers in any part of the gastrointestinal tract. Feeding enzyme increased trypsin (p=0.01), chymotrypsin (p=0.03) and amylase (p=0.08) levels in the jejunum. Chymotrypsin levels were higher (p=0.04) in the ileum of pigs fed enzyme. Serum glucose levels were lower (p=0.01) on day 14 in pigs fed enzyme either alone or in combination with acid. Under the conditions of this experiment (10% dietary whey, pigs weaned at 35 days of age), neither organic acid nor enzyme were effective in improving starter pig performance. Therefore, there would appear to be little justification for the routine inclusion of these products in diets fed to pigs weaned at 35 days or later.